dt-bindings: qcom_nandc: Add SDX55 QPIC NAND documentation

Qualcomm SDX55 uses QPIC NAND controller version 2.0.0 with BAM DMA
Engine.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Documentation/devicetree/bindings/mtd/qcom_nandc.txt

@@ -10,6 +10,8 @@ Required properties:
                             IPQ6018 SoC and it uses BAM DMA
     * "qcom,ipq8074-nand" - for QPIC NAND controller v1.5.0 being used in
                             IPQ8074 SoC and it uses BAM DMA
+    * "qcom,sdx55-nand"   - for QPIC NAND controller v2.0.0 being used in
+                            SDX55 SoC and it uses BAM DMA
 
 - reg:			MMIO address range
 - clocks:		must contain core clock and always on clock